Once a player has solved the grid, or run out of time, they get the chance to guess what connects each of the groups. This is an important part of the game that can really change whether the player enjoys a grid or not. In particular, if they know the answer but the system says they were wrong this can be very frustrating.
But as a setter it's easy to make sure the system always gets it right if you understand how it works.
The system looks at a users answer and looks for the linking terms specified by the setter.
For example lets imagine the grid contains the members Louis C.K., Lenny Henry, Jimmy Carr, George Carlin.
First think about things a user might type as the link between these:
Really try to think of as many possibilities as you can. Then it's a matter of finding the linking terms. Clearly you're not going to guess every permutation of how they will phrase things, that doesn't matter. If a linking term shows up anywhere in your list it will be successful. Here is what you should type for the linking terms for this group: comed, entertain, funny. This will match all of the above, and many more. Note the use of short forms - "comed" matches comedy and comedian, etc. Never enter a full phrase as a linking term.
Good luck and happy gridding!